Bună! ⚡
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[tex]a) 14-|-x+4|=8 <=> -|-x-4|=8-14 <=>[/tex]
[tex]<=> -|-x-4|=-6/*(-1)<=>[/tex]
[tex]<=> |-x-4|=6 =>\left \{ {{-x-4=-6} \atop {-x-4=6}} \right. =>\left \{ {{-x=-2} \atop {-x=10}} \right. => \left \{ {{x=2} \atop {x=-10}} \right.[/tex]
x ∈ {2, -10} ✔
[tex]b) -3(3x+1)+14=3(7x-3)-10 <=>[/tex]
[tex]<=> -9x-3+14=21x-9-10 <=>[/tex]
[tex]<=> -9x+11=21x-19 <=>[/tex]
[tex]<=> -9x-21x=-19-11 <=>[/tex][tex]<=> -30x=-30 => x=1[/tex]
x ∈ {1} ✔